I too junked most of what came with P6 & 7, the easiest way to get rid is simply to delete the relevant items from Runtime>Geometries, Textures and Library folders, most of it should be obvious in those locations, if you're not sure, load the items in Poser then on the main tool bar, click Windows> Python Scripts> Utility Funcs> create scene inventory. In the pop-up that appears, select> list
This will give you a list of whats loaded and locations, copy this to a notepad or print, close Poser and then start deleting. You might miss a few items here and there, but taking out Geom's, Tex and Characters will get rid of the bulk of space wasters.